A liquid crystal display device is used in various fields of applications as the device can be thin in thickness. In the liquid crystal display device, a TFT substrate on which pixel electrodes and thin-film transistors (TFTs) and the like are formed in a matrix state and a color filter substrate on which color filters and the like are formed at positions corresponding to the pixel electrodes face each other, and liquid crystal is sandwiched between the TFT substrate and the color filter substrate. Light transmittance corresponding to liquid crystal materials is controlled in units of pixels to thereby form an image.
In the TFT substrate, there are data lines extending in the vertical direction and arranged in the horizontal direction and scanning lines extending in the horizontal direction and arranged in the vertical direction, and pixels are arranged in an area surrounded by the data lines and scanning lines. Each pixel chiefly includes the pixel electrode and the thin-film transistor (TFT) as a switching device. A display area is formed by many pixels formed in the matrix state in the above manner.
The TFT substrate and the counter substrate are bonded together through a sealing material. In this case, a gap between the TFT substrate and the counter substrate is prescribed through columnar spacers formed in the counter substrate in the display area, thereby allowing a liquid crystal layer to be a given thickness. In the seal part, glass fibers are mixed into the sealing material, and the thickness of the seal part is prescribed by a diameter of glass fibers.
However, when a manner of determining the gap between the TFT substrate and the counter substrate differs in the display area and in the seal part, reliability of the seal part may be reduced as well as display unevenness may occur due to nonuniformity of the gap. Accordingly, there is proposed that, in JP-A-2010-139953 (Patent Document 1), the gap between the TFT substrate and the counter substrate in the display area and the seal part is made to be constant as well as reliability of the seal part is increased. It is also proposed that, in JP-A-2010-224491 (Patent Document 2), protrusions are provided to thereby prevent the spread of the seal.